Open AccessEvaluations of a Detector-Limited Digital Impedance Bridge
Author(s) -
Mona Feige,
Stephan Schlamminger,
B.C. Waltrip,
Michael Berilla,
Yicheng Wang
Publication year - 2021
Publication title -
journal of research of the national institute of standards and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.202
H-Index - 59
eISSN - 2165-7254
pISSN - 1044-677X
DOI - 10.6028/jres.126.006
Subject(s) - detector , electrical impedance , resistor , voltage , physics , noise (video) , optics , johnson–nyquist noise , acoustics , computer science , quantum mechanics , artificial intelligence , image (mathematics)
We tested a simple digital impedance bridge using two nominally equal resistors toform a 1:1 ratio. We focused on resolution and stability of the detectors. Fluctuationsof the source voltages were largely removed through postprocessing of the digitizeddata, and the measurement results were limited by the detector noise. Thisdetector-limited operating condition was first demonstrated using three modifiedKeysight 3458A multimeters for measurements of the voltage ratios, achieving 0.01 μV/Vtype A uncertainty in less than 15 min at 1 kHz. In an effort to extend the applicablefrequency range and develop a system with off-the-shelf components, we tested a systemusing three lock-in detectors for measuring small deviations from the perfect AC ratioof unity magnitude, achieving stabilities and resolutions of 0.1 μV/V in a few hours foreach point from 1 kHz to 5 kHz.